Heater.



' UNITED. STATES lPatented. January 31, 1905.

PATENT OFFICE.

HEATER.

SPECIFICATION forming part of Letters PatentI No. '781,5-00, dated January 31, 1905.

I Application filed March 24:,19011.` Serial No. 199,803.

To all whom t may concern'. Y

Be it known that I, WILLIAM H. DENsLow, a

y citizen of the United States, residing at WalIo verly, in the county of'lioga and State of New York, have invented new and useful Improvements in Heaters, of which the following is a specification.

This invention relates to hot-air heaters or furnaces especially adapted for domestic use; and the primary object of the same is toprovide simple and effective means .between the upper terminal of the ordinary fire-pot and the lower end of the. shell or inclosure forming the combustion-chamber to `increase the dimensions of the fire-pot in a vertical direction and permit a variation --in the depth of the fire-bed to accommodate changes in temperature by proportionately increasing the heating capacity .of theffurnace andtoprevent injury to and burning out of the lower extremity of the combustion-chamber shell or inclosure by removing the latter as far as possible from the greatest point of heat, this position of the lower extremity of the shell or 4 inclosure forming the combustion-chamber being also conducive to a uniformity in the `expansion and contractionof said inclosure.

VA further object is to generally improve the construction and -eiiiciency of heaters of the class to which the invention relates and utilize the products of combustion or smoke at the upper extremity of the combustionchamber for heating air fed to the furnace and passing into the-lower part of the outer Fig. 2 is ahorizontal section taken vin the The numeral l designates a base of suitable contour and having an opening 2 thereth rough,

the saidbase supporting a lire-pot 3 and ashpit 4C, included in .the lower portion of the heater. Agrate 5 of any suitable form is disposed in the upper portion of the ash-pit below the lower terminal of the fire-pot, and from said ash-pit a conduit 6 extends outwardly to a door 7, covering an opening 8 in the lower extremity of an outer casing 9. The outer casing is constructed of suitable sheet metal, as usual, and has a top closure 10 and as many collars 11 as may be desired for the attachment of hot-'air fiues. bar 12 from the grate 5 projects outwardly th rough the cond uit 6 and is accessible through the door 7. The ashes from the pit 4 may also be removed through the conduit 6 and door 7.

VThe lire-pot 3 is strengthened by aseries of external ribs 13, which increaseinoutward extent toward the upper extremity of said pot, where a flange or outwardly-projecting ledge 14 is formed and peripherally surrounded by an u pstanding guard 15. On the ledge 14 a suitable cast-metal hollow ring 16 is disposed and has an open bottom closed by saidledge. This ring provides a dead-air chamber at the A shaker rod or upper terminal of the iire-'potand also'serves The outer wall 17 of the ring is vertically straight, and the lower extremity of said wall bears against the inner surface of the guard l5.

vThe ring also has a reduced horizontally flat top 18, provided with an upstanding guardiiange 19, at a short distance from the periphery thereof, to provide an angular seat to receive the lower terminal of the shell or casing 20, forming theA combustion chamber 21.

4From the inner terminal of the top 18 the inner wall ofthe ring slopes downwardly atan angle of inclination toward Vthe center of the lire-pot, as at 22, and continues into a short vertical wall 23, having its inner surface Hush with the similar surface ofthe fire-pot 3. It will beseen that the ring 16 or the -dead-air chamber provided thereby locates the lower terminal of the shell or casing 20 at adistance above the upper terminal or ledge 14 of the vlire-pot 3, and by this disposition or arrange- 50 through the annular passage 33.

ment of the shell or casing 2() injury to or burning out of the lower terminal thereof is obviated and a regular expansion and contraction of said shell or casing ensues, thus 5 avoiding the formation of open joints between the parts directly cooperating with the firepot. An open joint between the ledge 14 and the lower open side or bottom of the ring 16 is avoided by reason of the inner and outer walls IO of said ring engaging or resting on the ledge at a distance from each other, and tendency to burning out of the ring 16 will also be prevented by reason of the dead-air chamber provided thereby; The {ire-bed capacity of I5 the heater or furnace is also materially increased by the interposition of the ring 16 between the fire-pot and the shell or casing of the combustion-chamber, and the heater in moderate weather may have a fire-bed therein 2O of limited vertical extent, or in very cold weather the fire-bed may project upwardly to the top of the ring without liability of injury to the shell creasing of the combustion-chamber. This is an important feature in furnace construction, as the heating capacity of furnaces havingre-pots of ordinary dimensions may be materially increased without modifying the remaining dimensions of furnaces. 1t will also beunderstood that the inner inclined portion 22 of the ring 16 effectively serves in directing the fuel into the fire-pot, and the narrow top 18 will reduce the tendency of the fuel to lodge thereon.

The shell or easing 2() has a dome-shaped cap 24, with a central enlarged opening 25 and smaller openings 26 in concentric relation thereto, the said openings 25 and 26 being surrounded by upstanding collars 27 and 28, respectively. A closed dome 29 is fitted over the collar 27, and engaging the collars 28 are lower reduced tubular necks 30, depending at regular intervals from the bottom 31 of an annular chamber 32. The dome 29 projects upwardly throughthe central open space 33 of the annular chamber 32 and forms, with the medium of a short iiue 35, opening intothc chamber 32 and having a damper 36 hinged at its upper end thereto and operative by means of a slidable rod 37, connected to the lower portion thereof and projecting outwardly through the outer wall of the chamber 32 and the outer casing 9.

The combustion-chamber 21 has a fuelchute 38 leading thereto at a downward angle of inclination and terminating at its upi per outer portion eoincidently with an opening 39 in the casing 9, the said opening being rendered accessible through the medium of a suitable door 40.

The produc-ts of combustion or smoke rising from the fire-pot and entering the combustion-chamber 21 pass from thelatter into the dome 29 and the chamber 32. and the air fed into the bottoni of the outer casing 9, through the medium of a suitable air-chute 41, is fully heated by coming in contact with the outer and inner walls of the chamber 32 and the said dome 29. It will be observed that the air passing between the bottoni of the chamber 32 and the cap 24 will be heated by said cap, as well as the bottom, and the heat of the air passing between the bottom of the chamber 32 and the cap 24 will be intelisified by passing upwardly through the annular passage 33 and rendered more eii'ective as a heating medium when it passes through the top 10 of the outer casing 9 into the hotair iiues. Through the medium of the daniper 36 the draft may be regulated in such manner as that the smoke and products of combustion may be checked in any tendency toward rapidly passing off into the sniokeflue before the full heating effect thereof has been obtained without in the leastimpairing the necessary draft, and particularly will this be so when high winds are blowing and the uptake and suction in the smoke pipe or liuc is increased above normal. Suliicient circulation of the smoke and products of combustion in the dome 29 will be set up by the draft of the furnace to allow new charges to successively replace each other therein, the smoke and products of combustion from the dome passing into the chamber 32 through the openings 26. This auxiliary heating attachment is very effective in the operation of the improved heater or furnace, as a greater heating-surface is provided. Moreover, the use of fuel is cconomized.

Changes in the proportions, dimensions, form, and minor details may be resorted to without departing from the spirit of the invention.

Having thus described the invention, what is claimed as new is- A heater comprising an outer casing having a top closure, a fire-pot in the casing having an outwardly-projecting ledge at its upper end, an upstanding guard surrounding the ledge, external ribs on the lire-pot increasing in upward extent toward their upper ends and bracing the ledge, a hollow ring having an open bottom resting upon the ledge inside the guard, said ring having a vertical outer wall, a reduced horizontal fiat top provided with an upstanding guard-flange and an inner wall inclined downwardly and terminatingin a short vertical wall resting on the inner periphery of the ledge, a shell or combustionchamber resting upon the hollow ring outside the guard-flange thereof, a dome-shaped cap IOC on the combustion-chamber, an annu-lar eham- In testimony whereof I affix my'signature in ber above the cap andbelowvthe top closureV presence oft-,W0 Witnesses. Y of the outer casing, tubular necks connecting the annular chamber Wththe shell, ,a dome WILLIAM Hf DENSLOW 5 surrounded by the annular chamber and cornv Witnesses: Inuneabng with the connbnstion-cham-ber,V and GHAS. HYER,

a het-air 'outlet over theannular chamber. JOHN L.- FLETCHER.- 

